Improvement in lifting-jacks



UNITED STATES PATENT OEEICE.

WILLIAM J. LANE, OF CHAPPAQUA, NEI/V YORK.

IMPROVEMENT IN LIFTING-JACKS.

Specification forming part of Letters Patent No. 30,484, dated October 23, 1860.

To @ZZ whom it may concern:

Be it known that I, WILLIAM J. LANE, of Chappaqua, in the county of Westchester and State of New York, have invented a new and Improved Lifting-Jack; and I do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the annexed drawings, making a part of this specilicatiou, in which- Figure l is a side sectional view of my invention, taken in the line x x, Fig. 2. Fig. 2 is a horizontal section of same, taken in the line y y, Fig..l.

Similar letters of reference indicate corresponding parts in the two figures.

This invention consists in the employment or use of a sliding clamp attached to a lever, having a movable fulcru 1n and fitted in a su itable stock, in connection with a slide-bar which passes through the clamp, and has its lower end itted in the stock, all the parts being arranged substantially as hereinafter fully shown and described, whereby a very simple and eiiicient portable lifting-jack is obtained, and one that may be readily manipulated and applied to its work.

To enable those skilled in the art to fully understand and construct my invention, I will proceed to describe it.

A represents an upright, which has a suit.- able base B, and is slotted longitudinally nearly its whole length, as shown at a, the slot extending from the baseB upward to a point b. This upright forms the stock of the implement, and at the upper end of the slot, within the upright or stock, there is secured by a joint c an arm C, through the upper end of which the fulcnrunI-pin d of a lever D passes.

To one end of the lever D there is attached by a pin or joint e a plate E, the inner edge of which has shoulders f, which bear against the side of the upright A. The tang g of the plate E has pins h in it, which project from its side and bear against the inner side of the upright or stock A, as shown clearly in Fig. 2. The pins h 7L are inserted inthe lower part of the tang g, for reasons hereinafter stated. The plate E has an opening i in it, through which a bar F passes. This opening may be in the form of a cross, as shown clearly in Fig. 2, and the bar F is of similar form in its transverse section. The lower end a* of the bar F is curved and passes through the slot a of the stock or upright A, and has a notch 7' in each side to receive the edges of the stock or upright A at each side of the slot a, said edges serving as guides for the bar F. The upper and lower surfaces of the plate E are concave, so as to cause the edge of the opening t' to be quite angular, as shown in Fig. l.

The operation is as follows: The upright or stock A is placed beneath the article to be raised, and the bar F is elevated by hand until its upper end comes in contact with said article. The lever D is then elevated, and the plate E thereby shoved down on the bar F, as shown in red, Fig. l. The lever D is then depressed and the plate E elevated, the plate as it rises clamping bar F, owing to the end pull or draw of thelever D and the canting position thereby given the plate, and the bar F is consequently elevated, and with it the article which rests on it. V'Vhen the lever D is fully depressed, the fulcrum-pin d, which is at the upper end of arm C, is beyond the pivot e, which connects the plate E with lever D, and consequently a self-acting lock is obtained and the bar F, with its weight, is retained. The weight and bar are lowered by elevating the lever D, and thereby moving the fulcrum CZ out or back from underneath the pivot e, as shown in red, Fig. l. The pins h h prevent the plate E from being canted upward and binding against the bar F when the latter is being moved upward and adjusted to Work by the operator. The pins h h will not allow the plate E to be shoved upward above a horizontal position.

I do not claim any of the within-described parts separately; but I do claim as new and desire to secure by Letters Patent The employment or use of the plate or clamp E, lever D, arm O, and bar F, applied to a stock or upright A, and all arranged essen, tially as and for the purpose herein set forth.

WILLIAM J. LANE. 1'Vitnesses:

THos. DEAN, JOHN F. CHILD. 

